Development and validation of the congestion quantifier seven-item test (CQ7): A screening tool for nasal congestion

Abstract

Objective: This study aimed to develop and validate a short, simple, patient-completed instrument for identifying patients with congestion in a 15-day study. Allergic rhinitis (AR) is the most common allergic condition worldwide, with congestion as one of the most salient symptoms. Nevertheless, there is no short screening tool designed specifically to identify congestion that can help patients make decisions about seeking treatment. Methods: Patients (N = 354) received a clinical exam to confirm congestion and assess its possible causes including confirmation of AR. They completed the 13-item draft of the Congestion Quantifier (CQ) and five additional patient-reported outcome instruments. Results: The 13-item draft CQ was reduced to a seven-item version, the CQ7. Internal consistency reliability was 0.93; test-retest reliability = 0.85. Construct validity wasdemonstrated by significant correlations with the Medical Outcomes Study Sleep Scale, the Work Productivity and Activity Impairment Questionnaire - Allergy Specific, and the Positive Affect and Negative Affect Scale Fatigue subscale (r = 0.23-0.67). The CQ7 can discriminate between controls and patients (AUC > 0.9). Moreover, it can discriminate between different levels of severity of symptoms of AR. A score of 7 provided optimum balance of sensitivity (91%), specificity (86%), and correct classification (90%) for detecting congestion. Conclusion: The CQ7 is reliable, valid, and responsive to differences in severity of nasal congestion. The CQ7 can identify patients with congestion that may need to be evaluated by a clinician. © 2007, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).